Countries that ban the smacking of children appear to be safer for young people to grow up in, according to research revealing that fighting between youths – particularly females – is less common where corporal punishment has been outlawed.

Experts say the study adds to a growing body of evidence that punishing children by smacking, slapping or spanking them can lead to later harm. The research has led to renewed calls for policymakers to ban such practices in both schools and the home.

“The association with academic problems and mental health problems and so on among those kids that have this experience in early life, that is pretty well established,” said Dr Frank Elgar, co-author of the research from McGill University in Canada. “Our question was about policy.”

However, researchers say it is not clear whether bans on smacking themselves drive better behaviour, or if smacking and youth violence were already rarer in countries that have adopted the policy.

“I cannot say that a country that decides to ban corporal punishment tomorrow is going to see a declining trend in youth violence,” said Elgar.

Writing in the journal BMJ Open, researchers in Canada, the US and Israel describe how they examined the results of surveys carried out in schools in 88 countries between 2003 and 2014. More than 400,000 young males and females were asked about how often they physically fought with others, with their ages ranging from 11 to 25 years depending on the survey.

The team then considered whether corporal punishment was legal in a given country, and if so, whether the ban was only in schools, or in the home as well.

20 of the countries had no ban, including Zimbabwe and Morocco, while 30 had a ban in all settings as of 2017, including Sweden and Tunisia. The UK was among those with a partial ban: in England hitting is banned but parents can use “reasonable punishment”, while Scotland and Wales are moving to close the loophole to pass a total ban on smacking.

The researchers found that boys were more than three times as likely to fight frequently than girls, meaning coming to blows four or more times in a year.

Such frequent fighting was less common among 13-year-old boys and girls in countries with a total ban on corporal punishment compared with those without, with 31% less fighting for boys and 58% less for girls. That said, when factors including national wealth, homicide rates and capital punishment bans were taken into account, a ban on corporal punishment only appeared to be linked to a drop in fighting among girls.

Elizabeth Gershoff, professor of human development and family sciences at the University of Texas at Austin, who was not involved in the study, said previous work has shown that corporal punishment can have serious consequences. “One of the strongest effects on children is increasing aggression – because being hit is an example of using aggression with other people, so children learn that,” Gershoff said. “It also is linked with a greater increase in mental health problems like depression or anxiety.”

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But Gershoff said while the international scale of the new study was impressive, the research did not look at how fighting among adolescents changed from before a ban to after it was introduced. She also said the study failed to consider whether, for countries with bans, the law was in place when the adolescents were young children – a time when smacking is most common.

“Unless the ban happened 10-15 years before the study, then they didn’t have an opportunity to really be affected by the ban,” she said.

Alana Ryan, senior public affairs and policy officer at the National Society for the Prevention of Cruelty to Children, said the study suggests national bans keep children safe from their peers as well as adults.

“Physical discipline should have no place in society and the defence of ‘reasonable punishment’ should be removed from law,” Ryan said. “It’s high time that the positive steps which Wales and Scotland have taken to keep our children safe are echoed across the rest of the UK.”